Photographic developing tank



Mar; 13, 1923.

G. F. FRAMJ EE'. PHOTOGRAPHIC DEVELOPING TANK.

fm/en/ar HLED JAN-4, I922- Patented Mar. 13, 1923.

UNITED STATES PATENT OFFICE.

GEORGE FEBOZA FRANZ-TEE, OF PALMERSTON NORTH, NEW ZEALAND, ASSIGNOR OF ONE-HALF TO ALBERT WATERWORTH, OF WELLINGTON, NEW ZEALAND.

PHOTOGBAPHIC DEVELOPING TANK.

Application filed January 4, 1922. Serial No. 527,035.

To all whom it may concern: 7

Be it known thatI. GEORGE FERozA ERAhI- JEE, subject of the King of Great Britain, residing at 1 Weston Avenue Palmerston North, in the Dominion of New Zealand, have invented new and useful Improvements in Photographic Developing Tanks, of which the following is a specification.

This invention relates to the tanks used for the daylight development of photographic films of that class in which the film in its rolled state, as taken from the camera, is inserted in the apparatus and drawn out so as to extend lengthwise therein with its sensitized surface exposed, and the developing solution is then added to the tank in order to act upon such film in the usual way.

The invention consists in a special construction of such a type of apparatus, involving special facilities for the insertion of the film roll, its unwinding in the tank, and also means for holding the film in the tank and for the removal of any air bubbles from the films surface during the developing operation.

The invention is illustratedin the accompanying drawings and will be hereinafter more fully described in relation thereto. In such drawings Figure 1 is a side elevation of the tank.

Figure 2 is a cross sectional elevation taken on the line 2-2 of Figure 1 and looking to the 'right of such line Figure 3 is a similar'section taken on the line 33 of Figure 1.

Figure 4 is a plan of the tank with the cover removed.

Figure 5 is a sectional elevation of: the tank.

Figures 6 to 9 are detail drawings of the spool holder, Figure 6 being aside elevation, Figure 7 one end view, Figure the other end view and Figure 9 a sectional lan. p In the views Figures 3, 4, 5 and 9 the film spool is shewn in position in the tank ready for its unwinding.

According hereto the tank A is formed of a deep narrow troughof a depth such as to conform with thewidth of the largest size film for which the tank is to be used, of a width such as to allow for the free doubling over of a film and its backing sheet between the inside walls, and of a length slightly greater than half the length of the longest film for which the tank is to be used. This tank A is open at its top and a light proof cover B is provided for fitting over such top and closing the tank. At one end of the tank it is broadened out to form a spool receiving chamber C, the cover B being shaped in correspondence with the shape of this chamber. Near this end also is a funnel D fitted on to the side of the tank and opening at its bottom end into the bottom of the tank at the chamber C so that the developing or other solutions may be introduced into the tank as required.

The spool receiving chamber C has a spool holder of special form fitted within it, such holder being constructed to hold the spool axis in such a manner as to allow for it unwindin and also having means whereby the end 0 the film backing sheet may be gripped and the film end and sheet looped topermit of it being engaged by the device employed for stretching the film through the tank. This spool holder is formed by a U-shaped plate E one vertical member E of which is made of extensible length and having its top end shaped to extend inwards. This top end and the bottom of the U beneath it are formed with pins 6 to fit into the usual trunnion holes formed in the ends of some forms of spools, or may be formed with bearings to receive the trunnion pins with which other forms of spools are made. -1

Thus a spool J may be arranged to extend up Within one side of this holder so that it may be turned on its own axis in the bearings embodied in such frame. The extensibility of the holder side will permit of it being adjusted to suit difi'erent lengths of spools and also for it opening out to receive the spool to be mounted therein. The other member F of the holder is formed as a grip for holding thefilm backing end J, such grip being made by constructing the holder side with slots f running longitudinally in itslength and with a spring tongue F dividing them so that the backing strip J may be intertwined in such slots andthere- .by held firmly against a lengthwise pull upon it, as shewn in Figure 9.

In fixing a film for operation in the tank it is placed thus in-the holder, the film backing then extending across the holder width between the spool and the grip. This holder then occupies a position in the tank end in which the loop in the backing extends at ios right angles across the mouth of the narrow portion of the tank extending from the spool chamber and it is so bent that its outer face is towards the outer end of suchcham: ber, as clearly shewn in Figure; 4.

Combined with the cover B to fit over the tank top, is a rod G that is "capable of extending throughout the length of the tank and is mounted in a carrier Gr fixed to the cover at its end corresponding to the spool chamber end so that it may slide longitu dinally therein and having a handle 9 on its outer end for operating it. The inner end of this rod tx' is furnished with a cross bar H at right angles extending down into the tank A for about the full-height thereof..

If necessary such bar may have a roller H mounted on its length.

In use, the rod 1s first drawn right out to one end of the cover while the cover is,

being placed on the tank, so that the bar H will pass down behind the backing strip J extending between the spool J and the grip F of the spool holder as indicated by the dotted lines in Figure at. Then when the cover has been placed in position, the rod is pushed in, causing the cross bar H to engage the film strip and to unwind the film from the spool sothat it extends along the tank length in a manner that is already The sensltized sur-' well known in the art. face of the. film is thus uncovered so that the developer solution with which the tank is charged may act thereon in the desired manner.

F or freeing the film surface from any air,

bubbles and also for agitating the solution, a second sliding rod K is arranged within the cover B in a similar mannerto that already described, by being arranged to slide in a sleeve It on the inside of the cover top. Thisrod, at its inner end, is provided with a pair of prongs M extending l'rom it at right angles fin parallel lines down into the tank. These are disposed at distance apart from one another such that the fihn as it is doubled and drawn out bythe unwinding .rod, will pass freely in between the forks. thus drawn out, the agitator rod is moved out and-in, anumberof times, its prongs passing loosely up over the surfaces of the doubled film and removing air bubbles and agitating the solution at the same time. This operation may be repeated at intervals during the time of development.

The tank, in addition to being used as. a developing tank, may beused for fixing the developed films by removing the developer solution, rinsing with water and then running the fixing solution in, all without removingthe film from the tank.

I claim 1. A photographic developing tank formed by a deep and narrow trough adapted to \Vhen therefore the film has been by a horizontally disposed narrow trough open at its top and formed with an enlarged spool holding chamber at one end, a spool holder adapte'dto fit'in such chamber and to hold a spool toturn on a vertical axis therein and so that its outer end, after passingacross the end oi the trough, is secured, a light tight cover for the trough, and a rod mounted to slide longitudinally through thecover and projecting through one end thereof and having a bar on its inner end extending down into the trough, substantially as specified,

3. A photographic developing tank formed by deep narrow trough opening at one end into an enlarged spool chamber, a cover adapted to fit over the said trough and chamber, means for the introduction oi a liquid intofthe trough when the cover is in position, a spool holder fitted into the spool chamber and formed by a U shaped plate, one member of which is adapted to journal. a spool upon a vertical axis and the other member of which is formed as a grip for holding the end of a film wound upon the spool, and

a rodmounted to slide longitudinally in the cover and to project through one end thereof having a bar projecting down from its inner end into the trough, substantially as specified.

l. In a photographic developing tank according to claim 1, a film spool holder con structed of a U shaped plate one vertical member of Wl11Cl1 is made extensible in length and with itstop end turned inwards,

journals at the top and bottom of such member, and the second vertical member of which is formed with a tongue extending longitudinally therein bet-ween sl ts, substantially as specified.

5. In a photographic deyeloping tank of the type described, a stirrer frame formed by a rod mounted to extend longitudinally within the tank cover and to project at one end through one end thereof and formed at its inner'end with two prongs extending vertically down into the tank trough, one near each ofthe respective sides thereof, substantially as specified.

In testimony whereof, I afiiX my ture.

signa- GEORGE 'FEROZA- FRAMJEE. 

